Stabilisation of chlorinated hydrocarbons



United States Patent 3,210,277 STABILISATION OF CHLORINATED HYDROCARBONSGeorge Edward 'Swift, Buncorn, England, assignor to Imperial ChemicalIndustries Limited, London, England, a corporation of Great Britain NoDrawing. Filed Aug. '10, 1964, Ser. No. 388,720 Claims priority,application Great Britain, Aug. 26, 1963, 33,698 63 Claims. (Cl.252-417) The present invention relates to the stabilisation ofchlorinated hydrocarbons. More particularly it relates to thestabilisation of liquid chlorinated long chain paraffinic hydrocarbonsfor use as oil additives.

It is known to improve the properties of mineral oil lubricants whenworking under heavy loads by incorporating therein a proportion ofrelatively involatile liquid chlorinated paraflinic hyrocarbon, forinstance a paraflinic hydrocarbon containing at least eight carbon atomsper molecule and chlorinated to a chlorine content of at least 25% byweight, particularly 4070% by weight. Although the extreme pressurelubricant properties of mineral oils are considerably improved by suchadditions, the improved lubricants are found to have the disadvantage ofstaining metal surfaces with which they come into contact in use, as forinstance in metal cutting and drawing operations and in lubricated gearassemblies.

We have now found that the aforementioned disadvantage can be avoided byincorporating in chlorinated parafiins that are to be employed as oiladditives a stabiliser system comprising a barium, calcium or magnesiumalkyl phenate and a sequestering agent.

According to the present invention a stabilised lubricating oil additivecomprises at least one liquid chlorinated parafiinic hydrocarboncontaining 826 carbon atoms per molecule and at least 25% by weight ofchlorine, 0.1-5 of a barium, calcium or magnesium alkyl phenate ashereinafter defined and 0.15% of an oil-soluble sequestering agent forheavy metals, the percentages of the said phenate and the saidsequestering agent being calculated on the weight of chlorinatedparaflinic hydrocarbon.

The barium, calcium and magnesium phenates employed in the presentinvention have in their simplest form the structure:

Where M is an atom of barium, calcium or magnesium, R is hydrogen or analkyl group containing 1-10 carbon atoms, and R is an alkyl groupcontaining 1-10 carbon atoms. When R as Well as R is an alkyl group Rwill usually be the same as R since such compounds are the more easilyprepared. The phenate employed may, however, contain additionally aproportion of sulphur in the form of a single sulphur linkage or adithio linkage between the two aromatic nuclei. The formulae of suchphenates may be represented by the following two structures I and II,such compounds being alternatively known as alkyl phenol sulphides anddisulphides:

3,210,277 Patented Get. 5, 1965 O l I R1 R1 Eta %112 where M, R and Rare as defined in the preceding paragraph.

Suitable sequestering agents are for instance the pentaerythritol estersof long chain fatty acids, such as oleic, stearic and lauric acids, andthe alkyl and aryl phosphites.

The alkyl phenate and the sequestering agent may each useful-1y beemployed to the extent of 5% by Weight of the chlorinated paraflinichydrocarbon, although for most applications 0.l1% by weight will befound to give adequate protection against metal staining. Greateramounts than 5% by weight may be employed but such amounts give notechnical advantage and in general they are not economic.

As stated hereinbet'ore, chlorinated paraflinic hydrocarbons containing826 carbon atoms per molecule and at least 25 by weight of chlorine maybe employed in the stabilised lubricating oil additives of theinvention. Of this range of compounds we prefer to employ for mostapplications those containing 40-70% by weight of chlorrne.

It is already known to add stabilisers to chlorinated hydrocarbons ofthe aforesaid range for the purpose of inhibiting decomposition by heat.It must be understood that chlorinated hydrocarbons stabilised accordingto the present invention may additionally contain conventional heatstabilisers, for example epoxidised oils.

We have found that if 0.15% by weight of a barium, calcium or magnesiumalkyl phenate is added to the chlorinated hydrocarbon without anaccompanying sequestering agent the staining of metal surfaces isprevented but that the heat stability of the chlorinated hydrocarbon (asdetermined by the standard test of measuring hydrogen chloride evolutionon blowing nitrogen through the material heated for 4 hours at C.) isthereby reduced, even when conventional heat stabilisers such asepoxidised oils are present. We have found, however, that addition of anoil-soluble sequestering agent for heavy metals prevents thisdeleterious eifect, possibly by inactivating barium, calcium andmagnesium chlorides which are thought to be formed in traces in therespective mixtures and to have a catalytic effect on decomposition ofthe chlorinated hydrocarbon.

The invention is illustrated by the following example but is not limitedthereby. A mixture of C C paraflins chlorinated to a chlorine content of65% by weight and containing 1% by weight of epoxidised oil as heatstabiliser is stabilised according to the present invention by additionthereto of 0.25% of barium octyl phenol sulphide and 0.25% ofpentaerythritol dioleate, the percentages being calculated on the weightof chlorinated paraffins. The stabilised chlorinated parafl'ln, whenadded in amount of 40% by weight to a mineral cutting oil provides aheavy duty cutting lubricant which gives no noticeable staining offerrous meta-1 parts.

What we claim is:

1. A stabilized lubricating oil additive which consists essentially ofat least one liquid chlorinated parafiinic hydrocarbon containing 8-26carbon atoms per molecule and about 25 to 70% by Weight of chlorine,0.l5% of a metal alkyl phenate wherein said metal is selected from thegroup consisting of barium, calcium and magnesium, and 0.15% of anoil-soluble sequestering agent for heavy metals, the percentages of saidphenate and said sequestering agent being calculated on the weight ofsaid chlorinated paraffinic hydrocarbon.

Z. A stabilized lubricating oil additive as claimed in claim 1 whereinsaid oil soluble heavy metal sequestering agent is selected from thegroup consisting of pentaerythritol esters of long chain fatty acids,alkyl phosphites and aryl phosphites.

3. A stabilized lubricating oil additive which consists essentially ofat least one liquid chlorinated paraflinic hydrocarbon containing 826carbon atoms per molecule and 4070% by weight of chlorine, 0.11% ofbarium octyl phenol sulphide and (ll-1% of pentaerythritol di oleate,the percentages being calculated on the Weight of chlorinated parafiinichydrocarbon.

4. A lubricating oil composition consisting essentially of a rnajoramount of a mineral cutting oil and a stabilizing amount of a stabilizedlubricating oil additive which consists essentially of at least oneliquid chlorinated paraffinic hydrocarbon containing 826 carbon atomsper molecule and 40-70% by weight of chlorine, 0.1-1% of barium octylphenol sulphide and 0.14% of pentaerythritol dioleate, the percentagesbeing calculated on the weight of chlorinated paraffinic hydrocarbon.

5. The lubricating oil as claimed in claim 4 wherein the stabilizedlubricating oil additive comprises about 40% by Weight of saidlubricating oil.

6. A stabilised lubricating oil additive according to claim 1 whereinthe said sequestering agent is a pentaerythritol ester of a long chainfatty acid.

7. A stabilised lubricating oil additive according to claim 1 whereinthe said sequestering agent is a phosphite selected from the groupconsisting of alkyl phosphites and aryl phosphites.

S. A stabilised lubricating oil additive as claimed in claim 10 whereinthe chlorinated paraffinic hydrocarbon component contains 40-70% byWeight of chlorine.

9. A stabilised lubricating oil additive as claimed in claim 10 whereinthe phenate is present to the extent of 0.14% by weight of thechlorinated paraflinic hydrocarbon.

ltl. A stabilised lubricating oil additive as claimed in claim 10wherein the sequestering agent is present to the extent of 0.11% byweight of the chlorinated paraffinic hydrocarbons.

References Cited by the Examiner UNITED STATES PATENTS 2,362,289 11/44Mikeska 25242.7

FOREIGN PATENTS 487,630 10/52 Canada. 749,3 54 5/56 Great Britain.

DANIEL E. WYMAN, Primary Examiner.

1. A STABILIZED LUBRICATING OIL ADDITIVE WHICH CONSISTS ESSENTIALLY OFAT LEAST ONE LIQUID CHLORINATED PARAFFINIC HYDROCARBON CONTAINING 8-26CARBON ATOMS PER MOLECULE AND ABOUT 25 TO 70% BY WEIGHT OF CHLORINE,0.1-5% OF A METAL ALKYL PHENATE WHEREIN SAID METAL IS SELECTED FROM THEGROUP CONSISTING OF BARIUM, CALCIUM AND MAGNESIUM, AND 0.1-5% OF ANOIL-SOLUBLE SEQUESTERING AGENT FOR HEAVY METALS, THE PERCENTAGES OF SAIDPHENATE AND SAID SEQUESTERING AGENT BEING CALCULATED ON THE WEIGHT OFSAID CHLORINATED PARAFFINIC HYDROCARBON.